Electrical connector and method of making same

ABSTRACT

An electrical connector includes a body means having means for securing an electrical member thereto. The body means is formed of a zinc base alloy comprising aluminum, copper, cadmium, tin, lead, magnesium, iron and zinc within certain critical ranges. The zinc alloy is heated to a molten state and the molten alloy is then pressure or gravity molded, subjected to fast chilling and chemically threated to form an electrical connector free from corrosion.

United States Patent Haegert 1451 Apr. 11,1972

[5 ELECTRICAL CONNECTOR AND METHOD OF MAKING SAME [72] Inventor: Clarence B. Haegert, 121] Elm Street,

Coffeyville, Kans. 67337 [22] Filed: Feb. 27, 1970 21] Appl. NO.I 15,267

[52] us. 01. ..339/230 0, 75/178, 148/32, 339/278 c 511 Int. Cl ..C22c 17/00, H011 11/26 [58] Field ofSearch ..136/134, 135; 339/224, 278 c, 339/230 0; 75/178; 148/32 [56] References Cited UNITED STATES PATENTS 291,286 1/1884 Brewer ..339/278 C X 1,467,651 9/1923 Prax ..339/224 2,095,825 10/1937 McRae ..339/278 c x 3,175,181 3/1965 Grabbe ..339/27 8 c I FOREIGN PATENTS 0R APPLICATIONS 144,280 11/1951 7111565116-; ..l36/l35R 650,211 9/1928 France ..l36/l34 736,907. 9/1955 Great Britain ..l36/135R omen PUBLlCATlONS Handbook of Engineering Materials, Miner et al., 1955, John 'Wiley & Sons, lnc., N.Y., pp. 2- 353 to 2- 36.1.

Primary Examiner-Charles N. Lovell Attorney-Shoemaker & Mattare [57] ABSTRACT An electrical connector includes a body means having means for securing an electrical member thereto. The body means is formed of a zinc base alloy comprising aluminum, copper, cadmium, tin, lead, magnesium, iron and zinc within certain critical ranges. The zinc alloy is heated to a molten state and the molten alloy is then pressure or gravity molded, subjected to fast chilling and chemically threated to form an electrical connector free from corrosion.

4 Claims, 57 Drawing Figures ELECTRICAL CONNECTOR AND METHOD OF MAKING SAME BACKGROUND OF THE INVENTION This application is a continuation in part of application, Ser. No. 610,878 filed Jan. 23, 1967, now abandoned.

The present invention relates to electrical connectors of various types and to the method of making them. Electrical connectors of this type including means for securing an electrical member thereto have in the past been generally formed of a brass-lead alloy or a copper alloy. Such prior art connectors are relatively expensive and are subject to excessive corrosion, particularly in an environment containing sulphuric SUMMARY OF THE INVENTION The present invention relates to an electrical connector and the method of making the electrical connector wherein the body means thereof is formed of a zinc base alloy manufactured in a particular manner. This utilization of the zinc base alloy of the present invention substantially reduces the cost of the connector since the materials involved are cheaper, and furthermore, the connector can be readily manufactured by sand casting or die casting.

Also, surprisingly enough, it has been found that electrical connectors made of such a zinc base alloy according to the present invention have better electrical conductivity than prior art connectors made of a brass lead alloy or a copper alloy, and also exhibit good tensile strength. Additionally, the connector of the present invention has very good resistance to corrosion even when it comes in contact with sulphuric acid, which is normally highly corrosive to zinc and zinc base alloys.

An object of the present invention is to provide a new and novel electrical connector having good electrical conductivity, good tensile strength, and further which is resistant to corrosion.

A further object of the present invention is to provide a 1 unique electrical connector made of a zinc base alloy which is resistant to corrosion by sulphuric acid.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a top perspective view illustrating a first form of electrical connector or battery terminal according to the present invention;

FIG. 2 is a top perspective view illustrating a second form of electrical connector or battery terminal according to the present invention;

FIG. 3 is a top perspective view of a further electrical connector according to the present invention;

FIG. 4 is a top perspective view of still another electrical connector according to the present invention;

FIG. 5 is a top perspective exploded view of the structure illustrated in FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings wherein like reference characters designate corresponding parts throughout the several views, a first form of electrical connector is illustrated in FIG. 1 wherein the connector is indicated generally by reference numeral 12 and comprises a battery terminal.

This connector or battery terminal includes a body means 14 having an integral hollow cylindrical portion 16 for receiving an electrical cable or the like. The body means is also bifurcated at one end to form a pair of spaced integral leg portions 18 and 20 having a tapered bore 24 defined therebetween for receiving the post of a battery whereby the device is adapted to operate as a conventional battery terminal connector, as for example on a storage battery.

A bolt 30 extends through aligned holes provided in the outer ends of legs 18 and 20, the bolt 30 having an enlarged head portion 32 received within a cutout 34 provided in the outer surface of leg portion 20 of the body means. A nut 36 is threaded on the far end of the bolt as seen in FIG. 1 for clamping the connector on a battery post.

A small screw 40 is adapted to be threaded into a tapped hole provided in enlarge head 32 for securing a lug 42 tothe battery terminal. This lug has a suitable hole provided therein for receiving the threaded shank portion of screw 40. The end portion 44 of lug 42 is hollow for receiving a suitable electrical member which is crimped thereto.

A threaded stud 50 extends upwardly from portion 16 of the battery terminal and has a tapped hole formed therein for receiving a small screw 52 which is employed for holding lug 54 in place, lug 54 being of substantially the same construction as lug 42.

Referring now to FIG. 2 of the drawing, a modified electrical connector or batter terminal is indicated generally by reference numeral 60. This battery terminal includes a body means 62 having a hollow cylindrical portion 64 for receiving an electrical cable or the like. The body means also includes a pair of spaced leg portions 66 and 68 having aligned holes 70 and 72 formed therethrough for receiving a suitable nut and bolt assembly for clamping the battery terminal on a battery post.

A tapered bore 74 is formed between spaced legs 66 and 68 for receiving a conventional battery post.

Referring now to FIG. 3, a further modified form of electrical connector according to the present invention is illustrated. The electrical connector is indicated generally by reference numeral and includes a body means including a flat end portion 82 having a hole 84 formed therethrough. The opposite end portion 86 of the body means is of generally cylindrical configuration and is hollow for receiving a cable or the like, the bared end of the cable being crimped in position within such hollow end portion of the body means.

Referring now to FIGS. 4 and 5, a still further modified form of electrical connector is illustrated. The connector is in dicated generally by reference numeral 90 and includes a three-part body means, the body means including a bolt 92 having an enlarged hex head 94 at one end thereof and having a longitudinally extending slot 96 formed therein. The external portion of the lower part of the bolt is provided with threads 98.

The body means includes an intermediate member 100 the main portion of which is adapted to slide within the slot 96 formed in bolt 92. Member 100 includes depending leg portions 102 and 104 which are spaced apart and which are adapted to be inserted through a threaded bore 106 provided in a nut 108 and then turned upwardly as indicated in phantom lines in FIG. 5 so as to retain members 100 and 108 in assembled relationship as seen in FIG. 4. The threaded bore 106 is adapted to be threaded on the external threads 98 provided on the bolt 92.

As seen most clearly'in FIG. 5, the upper'surface of member 100 is provided with a central generally V-shaped groove or notch 110. A pair of lugs 112 extend outwardly in opposite directions from one end of member 100, and a similar pair of lugs 114 extend outwardly in opposite directions from the opposite end of member 100. The portion of member 100 between lugs 112 and 114 is adapted to fit within the slot 96 provided in bolt member 92, lugs 112 and 114 serving to .retain member 100 in position and to guide its movement in a vertical direction as seen in the drawings. It is apparent that when the electrical connector is in the assembled relationship shown in FIGS. 4, rotation of nut 108 with respect to bolt 92 will cause member 108 to be raised and lowered within the slot-96 in the bolt member whereby a suitable electrical member may-be clamped between the notch in the upper surface of member 100 and the undersurface of the hex head 94 of the bolt.

The body means of each of the electrical connectors as described in connection with FIGS. ll through 5 inclusive is formed of a zinc base alloy having a particular composition.

EXAMPLE I Aluminum 3.9 to 4.3% Copper 0.75 to 1.25% Magnesium 0.03 to 0.06% lron Up 0,0759: maximum Lead Up to 0.003% maximum Cadmium Up to 0.003% maximum Tin Up to 0.002% maximum Zinc Balance EXAMPLE 11 Aluminum 3.5 to 4.5% Copper 2.5 to 3.5% Magnesium 0.02 to 0.10% lron Up to 0.100% maximum Lead Up to 0.007% maximum Cadmium Up to 0.005% maximum Tin Up to 0.005% maximum Zinc Balance EXAMPLE llI Aluminum 3.9 to 4.3% Copper Up to 0.10% maximum Magnesium 0.3 to 06% Iron Up to 0.075% maximum Lead Up to 0.003% maximum Cadmium Up to 0.003% maximum Tin Up to 0.002% maximum Zinc Balance In each of the above examples, the percentages are by weight of the composition, and it will be noted that in each case the major portion of the composition comprises zinc which is the balance of the composition in each of the three examples.

In the present invention, the method of making the electrical connector includes the steps of heating one of the aforedescribed alloys to a molten state at a particular temperature, pressure or gravity molding the molten alloy at a particular pressure and for a specific time to form an electrical connector, subjecting the molded or injected connector to fast chilling to keep the grain structure of the connector very fine, and then chemically treating the connector in a suitable chemical bath to seal the pores of the connector against penetration and intergranular corrosion by sulphuric acid.

Specifically, the method of making the electrical connector includes the steps of heating one of the aforedescribed alloys to a molten state at about 765 F. A steel cavity mold is heated at about 450 F. and maintained within close limits at this temperature by means of circulating cooling water or the like around the cavity mold. The temperature of the molten alloy within the mold should not vary more than about :4 F. because the hardness and tensile strength of the metal increase at lower temperatures and decrease at higher temperatures.

The molten alloy is injected into the mold and subjected to 100 tons of pressure for about 1.4 seconds while in the mold and is then kept in the mold for a dwell time of about another 2.8 seconds with this pressure released and while maintaining the temperature of the mold at about 450 F., allowing the metal to solidify. This procedure increases the density of the metal and insures proper porosity of the metal.

The heat from the molten alloy is transferred to the mold and hence to the circulating cooling water and the pressures and temperatures to which the metal is subjected give the metal impact resistance and elongation.

The solidified metal is quenched immediately after its removal from the mold, which increases the mechanical properties of the metal at least 7,500 pounds per square inch higher than if allowed to cool in air.

After the quenching operation, the metal is subjected to a chemical treatment in a bath of trichloroethylenecarbon tetrachloride to seal the surface of the metal against penetracorros1on by sulphuric acid and the tron and intergranular like.

The cycle of injecting the molten metal into the mold, subjecting the metal to the pressure at. the times stated and removing the metal from the mold is controlled by a series of automatic timers. The mold cavity is thus automatically prepared for another injection of molten metal into the cavity under 2,000 pounds of exerted pressure.

It is apparent from the foregoing that there is provided a new and novel electrical connector body means having means for securing an electrical connector member thereto and wherein the body means is formed of a zinc base alloy which enables the connector to be manufactured at a lower cost with good electrical conductivity, good tensile strength, and good corrosion resistance characteristics.

As this invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, and since the scope of the invention is defined by the appended claims, all changes that fall within the metes and bounds of the claims or that form their functional as well as conjointly cooperative equivalents are therefore intended to be embraced by those claims.

lclaim:

l. A storage battery terminal connector comprising: a body means having cable connecting means for securing an electrically conductive battery cable thereto, said body means also including means for attaching the tenninal to a storage battery post, said body means being formed of a zinc base alloy comprising about 3.5 to 4.5 percent aluminum, about 0.02 to 0.10 percent magnesium, up to about 0.10 percent iron, up to about 0.007 percent lead, up to about 0.005 percent cadmium, up to about 0.005 percent tin, up to about 3.5 percent copper, the balance being zinc, all of said percentages being by weight of the composition, said connector being pressure molded and subsequently fast chilled to achieve a fine grain structure and chemically treated in a bath of trichlorethylenecarbon tetrachloride to seal the pores against penetration and intergranular corrosion by sulfuric acid, thus resulting in a battery terminal connector having high strength and electrical conductivity and good corrosion resistance.

2. A storage battery terminal connector as defined in claim 1 wherein the amount of aluminum is within the range of about 3.9 to 4.3 percent, the amount of magnesium is within the range of about 0.03 to 0.06 percent, and wherein there is no more than about 0.075 percent iron, no more than about 0.003 percent lead, no more than about 0.003 percent cadmium, no more than about 0.002 percent tin, and wherein the amount of copper is within the range of about 0.75 to 1.25 percent.

3. A storage battery terminal connector as defined in claim 1 wherein the amount of copper is within the range of about 2.5 to about 3.5 percent.

4. A storage battery terminal connector as defined in claim 1 wherein the amount of aluminum is within the range of about 3.9 to 4.3 percent, the amount of magnesium is in the range of about 0.3 to 0.6 percent, and wherein there is no more than about 0.075 percent iron, no more than about 0.003 percent lead, no more than about 0.003 percent cadmium, no more than about 0.002 percent tin, and no more than about 0.10 percent copper. 

2. A storage battery terminal connector as defined in claim 1 wherein the amount of aluminum is within the range of about 3.9 to 4.3 percent, the amount of magnesium is within the range of about 0.03 to 0.06 percent, and wherein there is no more than about 0.075 percent iron, no more than about 0.003 percent lead, no more than about 0.003 percent cadmium, no more than about 0.002 percent tin, and wherein the amount of copper is within the range of about 0.75 to 1.25 percent.
 3. A storage battery terminal connector as defined in claim 1 wherein the amount of copper is within the range of about 2.5 to about 3.5 percent.
 4. A storage battery terminal connector as defined in claim 1 wherein the amount of aluminum is within the range of about 3.9 to 4.3 percent, the amount of magnesium is in the range of about 0.3 to 0.6 percent, and wherein there is no more than about 0.075 percent iron, no more than about 0.003 percent lead, no more than about 0.003 percent cadmium, no more than about 0.002 percent tin, and no more than about 0.10 percent copper. 